def no_teen_sum(a, b, c):
  if a >= 13 and a <= 19:
    if a == 13 or a == 14 or a == 17 or a == 18 or a == 19:
      a = 0 
  if b >= 13 and b <= 19:
    if b == 13 or b == 14 or b == 17 or b == 18 or b == 19:
      b = 0 
  if c >= 13 and c <= 19:
    if c== 13 or c == 14 or c == 17 or c == 18 or c == 19:
      c = 0  
  return a + b + c
  